In this work, we show how parallel applications can be implemented efficiently using task parallelism. We also evaluate the benefits of such parallel paradigm with respect to other approaches. We use the PARSEC benchmark suite as our test bed, which includes applications representative of a wide range of domains from HPC to desktop and server applications. We adopt different parallelization techniques, tailored to the needs of each application, to fully exploit the task-based model. Our evaluation shows that task parallelism achieves better performance than thread-based parallelization models, such as Pthreads. Our experimental results show that we can obtain scalability improvements up to 42% on a 16-core system and code size reductions up to 81%. Such reductions are achieved by removing from the source code application specific schedulers or thread pooling systems and transferring these responsibilities to the runtime system software.

Abstract:

This work has been partially supported by the European Research Council under the European Union 7th FP, ERC Grant Agreement number 321253, by the Spanish Ministry of Science and Innovation under grant TIN2012-34557, by the Severo Ochoa Program, awarded by the Spanish Government, under grant SEV-2011-00067 and by the HiPEAC Network of Excellence. M. Moreto has been partially supported by the Ministry of Economy and Competitiveness under Juan de la Cierva post-doctoral fellowship number JCI-2012-15047, and M. Casas is supported by the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government
of Catalonia and the Co-fund programme of the Marie Curie Actions of the 7th R&D
Framework Programme of the European Union (Contract 2013 BP B 00243). Finally,
the authors are grateful to the reviewers for their valuable comments, to the people
from the Programming Models Group at BSC for their technical support, to the RoMoL team, and to Xavier Teruel, Roger Ferrer and Paul Caheny for their help in this work.